Python API documentation updates: a description of class hierarchy

was added to the docstrings of most Python extension types.

source/blender/freestyle/intern/python/StrokeShader/BPy_ConstrainedIncreasingThicknessShader.cpp

@@ -11,6 +11,8 @@ extern "C" {
 //------------------------INSTANCE METHODS ----------------------------------
 
 static char ConstrainedIncreasingThicknessShader___doc__[] =
+"Class hierarchy: :class:`StrokeShader` > :class:`ConstrainedIncreasingThicknessShader`\n"
+"\n"
 "[Thickness shader]\n"
 "\n"
 ".. method:: __init__(iThicknessMin, iThicknessMax, iRatio)\n"